An liquid crystal display (LCD) panel employs a number of thin film transistors (TFTS) to control light transmittance of pixels of the LCD panel. Each TFT usually includes a channel layer and an etch stop layer formed on the channel layer. The etch stop layer is used to prevent the channel layer from being etched. However, a specific mask is need to make the etched layer and the specific mask must be precisely aligned with the channel layer, which increases LCD panel cost.